Phenoxyacetate peracid precursors and perhydrolysis systems therewith

ABSTRACT

A perhydrolysis system is provided which includes peroxyacid precursors and a source of peroxygen. Upon dissolution in water these compositions provide high yields of a novel peroxyacid having the structure ##STR1## where R is hydrogen or an alkyl of not more than 5 carbon atoms. The precursors may include hydroxyl nitrogen derivatives as leaving groups, since the α-substituted phenoxy moiety enhances carbonyl reactivity toward perhydroxyl anion.

This is a division of application Ser. No. 045,197, filed Apr. 30, 1987,now U.S. Pat. No. 4,859,800, which is a continuation-in-part of Ser. No.927,856, filed Nov. 6, 1985, now abandoned.

FIELD OF THE INVENTION

The present invention relates to peroxyacids, and particularly toα-substituted peroxyacid precursors which will react with peroxide anionin aqueous solution to form the desired peroxyacid in situ.

BACKGROUND OF THE INVENTION

Peroxy compounds are effective bleaching agents, and compositionsincluding mono- or di-peroxyacid compounds are useful for industrial orhome laundering operations. For example, U.S. Pat. No. 3,996,152, issuedDec. 7, 1976, inventors Edwards et al., discloses bleaching compositionsincluding peroxygen compounds such as diperazelaic acid anddiperisophthalic acid.

Peroxyacids have typically been prepared by the reaction of carboxylicacids with hydrogen peroxide in the presence of sulfuric acid. Forexample, U.S. Pat. No. 4,337,213, inventors Marynowski et al., issuedJune 29, 1982, discloses a method for making diperoxyacids in which ahigh solids throughput may be achieved.

However, granular bleaching products containing peroxyacid compoundstend to lose bleaching activity during storage, due to decomposition ofthe peroxyacid. The relative instability of peroxyacid presents aproblem of storage stability for compositions consisting of or includingperoxyacids.

One approach to the problem of reduced bleaching activity of peroxyacidcompositions has been to include "activators" for or precursors ofperoxyacids. U.S. Pat. No. 4,283,301, inventor Diehl, issued Aug. 11,1981, discloses bleaching compositions including peroxygen bleachingcompounds, such as sodium perborate monohydrate or sodium perboratetetrahydrate, and activator compounds such as isopropenyl hexanoate andhexanoyl malonic acid diethyl ester. However, these bleach activatorstend to yield an unpleasant odor under actual wash conditions. U.S. Pat.No. 4,486,327, inventors Murphy et al., issued Dec. 4, 1984, and U.S.Pat. No. 4,536,314, inventors Hardy et al., issued Aug. 20, 1985,disclose certain alpha substituted derivatives of C₆ -C₁₈ carboxylicacids which are said to activate peroxygen bleaches and are said toreduce malodor.

U.S. Pat. No. 4,539,130, inventors Thompson et al., issued Sept. 3, 1985(and its related U.S. Pat. No. 4,483,778, inventors Thompson et al.,issued Nov. 20, 1984) disclose chloro, methoxy or ethoxy subsituted onthe carbon adjacent to the acyl carbon atom. U.S. Pat. No. 3,130,165,inventor Brocklehurst, issued Apr. 21, 1964, also discloses anα-chlorinated peroxyacid, which is said to be highly reactive andunstable.

European Patent Application 166,571, inventors Hardy et al., publishedJan. 2, 1986, discloses peracids and peracid precursors said to be ofthe general type RXAOOH and RXAL, wherein R is said to be a hydrocarbylgroup, X is said to be a hetero-atom, A is said to be a carbonylbridging group, and L is a leaving group, such as an oxybenzenesulfonate. C₆ through C₂₀ alkyl substituted aryl are said to bepreferred as R, with C₆ -C₁₅ alkyl said to be especially preferred foroxidative stability.

Various compounds have been disclosed in the prior art that containnitrogen as part of peroxygen precursor leaving groups. Murray, U.S.Pat. No. 3,969,257, Gray, U.S. Pat. No. 3,655,567, Baevsky, 3,061,550,and Murray, U.S. Pat. No. 3,928,223 appear to disclose the use of acylgroups attached to nitrogen atoms as leaving groups for activators. InFinley et al., U.S. Pat. No. 4,164,395, a sulfonyl group is attached tothe nitrogen atom of the leaving group. The activator structure is thusa sulfonyl oxime. Dounchis et al., U.S. Pat. No. 3,975,153 teaches theuse of isophorone oxime acetate as a bleach activator. It is claimedthat this isophorone derivative results in an activator of low odor andlow toxicity. In Sarot et al., U.S. Pat. No. 3,816,319, the use ofdiacylated glyoximes are taught.

In sum, many different peracid activators or precursors have beenproposed. However, there remain a number of problems for commerciallyfeasible applications. Among these problems are that the known peroxygenactivators and precursors have been difficult to prepare on a commercialscale, have been made from relatively expensive or toxic raw materials,have tended to yield an unpleasant odor under wash conditions, or havebeen found to provide impractically low yields of peroxyacid in situ.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide odorless peroxyacidprecursors that are readily prepared from relatively inexpensive rawmaterials, and give excellent yields in situ of peroxyacid whendissolved with a source of peroxide in water.

It is a further object of the present invention to provide a shelfstable, dry bleaching and/or laundering composition that gives effectiveperoxygen bleaching in laundering operations, even at low temperaturewash or bleaching solutions.

These and other objects are provided by the present invention.

In one aspect of the present invention, a perhydrolysis system for insitu generation of peroxyacid comprises: a peroxyacid precursor whichincludes at least one α-substituted carbonyl moiety with the structure##STR2## wherein R is hydrogen or a alkyl with 5 or less carbon atoms;and, a source of peroxygen which will react with the peroxyacidprecursor in aqueous solution to form a peroxyacid having the structure##STR3##

The inventive perhydrolysis system preferably provides yields of atleast about 75% of peroxyacid from the peroxyacid precursor at pH 9.5,even at low wash temperatures such as 21° C., and provides considerableflexibility in the choice of particular leaving group.

It is believed that the phenoxy moiety, which is substituted on theα-carbon of the acetate moiety, enhances the overall reactivity towardthe perhydroxyl anion. It is believed that this enhanced reactivitypermits the flexibility of choice for leaving groups. Thus, peroxyacidprecursors of the invention may be prepared with derivatives of oximes,N-hydroxyimides or amine oxides as leaving groups. These hydroxylnitrogens are less expensive than phenol sulfonates, and can providebetter storage stability for the peroxyacid precursors including suchhydroxyl nitrogen derivatives. Substituted or unsubstituted phenolderivatives as leaving groups are also within the scope of theinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

One aspect of the present invention is a perhydrolysis system for insitu generation of certain peroxyacids. By "perhydrolysis" is meant thereaction of a selected peroxyacid precursor with peroxide to form aperoxyacid. This reaction is in situ in that it occurs when theperoxyacid precursor is dissolved in sufficient water along with thesource of peroxide. It is important that the perhydrolysis reaction besubstantially complete within not more than about five minutes even atrelatively low temperatures, to permit sufficient bleaching time duringa normal washing machine wash cycle.

Normally, when the conjugate acids of leaving groups have a relativelyhigh pK_(a) (on the order of 11-13), then there would not be sufficientreactivity to provide adequate perhydrolysis. However, having theα-phenoxy substituent enhances reactivity such that even relatively highpK_(a) 's of 11 to about 13 provide precursors of the invention withexcellent yields of peroxyacid. The structure of the peroxyacid formedis shown by Formula I. The detection and quantitative determination ofthe inventive peroxyacid illustrated by Formula I was done according tothe procedure outlined in Organic Peroxides, Vol. I, Daniel Swern,Editor, Wiley-Interscience, New York (1970), p. 501. ##STR4##

The peroxyacid precursors of the invention yielding the Formula Iperoxyacid will sometimes be referred to as phenoxyacetate peroxyacidprecursors. This is because these inventive precursors may be viewed asα-substituted, acetic acid analogs with the α-substituent being aphenoxy moiety. This phenoxy moiety may have an alkyl substituent(branched or straight) of not more than 5 carbon atoms. Thus, the Rsubstituent shown in Formula I and throughout this specification may behydrogen or, as just explained, an alkyl of not more than 5 carbonatoms. Such peroxyacid precursors include at least one α-substitutedcarbonyl moiety with the structure illustrated by Formula II, where L isa leaving group. ##STR5##

The carbonyl carbon of Formula II is preferably esterified, and willhave the leaving group bonded through the ester linkage. Suitableleaving groups will be exemplified hereinafter.

The α-position substitution is important. For example, if one were tosubstitute the phenoxy group directly to the carbonyl carbon, then anundesired peroxyacid could be formed as a consequence of the phenoxyacting as a leaving group rather than an esterified, desired leavinggroup. For another example, if one were to substitute the phenoxy at theβ-position, then the variety of choice for suitable leaving groups wouldbe greatly diminished.

The α-substituted carbonyl moiety illustrated by Formula II can beprepared from readily available starting materials such as phenol andchloroacetic acid, as generally illustrated by Reaction Scheme I, toform a phenoxyacetic acid to which a leaving group will then be bonded.##STR6##

A variety of leaving groups may then be included in the phenoxyaceticacid molecule, usually by a condensation reaction, to yield theresultant peroxyacid precursor. Suitable leaving groups includederivatives of substituted or unsubstituted phenols, oximes,N-hydroxyimides, and amine oxides. It has been discovered that theoxime, N-hydroxyimide and amine oxide derivatized leaving groups arealso useful in certain other peroxygen bleach compositions, as describedin copending Application Serial No. 928,065, inventor Zielske, filedNov. 6, 1986, entitled "ACYLOXYNITROGEN PERACID PRECURSORS", of commonassignment herewith, and in copending Application Serial No. 928,070,inventors Fong et al., filed November 6, 1986, entitled "GLYCOLATE ESTERPERACID PRECURSORS", also of common assignment herewith.

A particularly preferred unsubstituted phenol for this invention isresorcinol, although other dihydroxybenzenes (e.g. hydroquinone) arefeasible for derivatization in forming these peroxyacid precursors.

Substituted phenols may be substituted with solubilizing groups, such ascarbonate, sulfonate, sulfate and quarternary nitrogen, and/or may besubstituted with straight or branched chain alkyls with about 1 to 6carbons or alkoxys with about 1 to 10 carbons. Illustrated substitutedphenols include p-phenolsulfonic acids and salts thereof,o-phenolsulfonic acids and salts thereof, p- and o-hydroxybenzoic acidsand salts thereof, 4-(trimethylammonium chloride)-phenol,4-(trimethylammonium bromide)-phenol, 4-(trimethylammoniumhydroxide)-phenol and 4-(trimethylammonium iodide)phenol.

Oximes of aldehydes or ketones are suitable in forming the leavinggroup, and illustrative oximes include acetaldoxime, benzaldoxime,propionaldoxime, butyaldoxime, heptaldoxime, hexaldoxime, phenylacetaldoxime, p-tolualdoxime, anisaldoxime, carpoaldoxime, valeraldoxime,p-nitrobenzaldoxime, acetone oxime, methyl ethyl ketoxime, 2-pentanoneoxime, 2-hexanone oxime 3-hexanoneoxime, cyclohexanone oxime,acetophenone oxime, benzophenone oxime, and cyclopentanone oxime.

Illustrative N-hydroxyimides include N-hydroxysuccinimide, N-hydroxyphthalimide, N-hydroxy glutarimide, N-hydroxy napthalimide, N-hydroxymaleimide, N-hydroxy diacetylimide and N-hydroxy diproprionylimide.

Illustrative amine oxides include pyridine N-oxide, 3-picoline N-oxide,trimethylamine N-oxide, 4-phenyl pyridine N-oxide, decyldimethylamineN-oxide, dodecyl dimethylamine N-oxide, tetradecyl dimethylamineN-oxide, hexadecyl dimethylamine N-oxide, octyl dimethylamine N-oxide,di(decyl)methylamine N-oxide, di(dodecyl)methylamine N-oxide,di(tetradecyl)methylamine N-oxide, 4-picoline N-oxide, and 2-picolineN-oxide.

Particularly preferred peroxyacid precursors with an unsubstitutedphenol derivative as leaving group are illustrated by Formulas III.##STR7##

Particularly preferred peroxyacid precursors with a substituted phenolas leaving group are illustrated by Formula IV, where R₂ is hydrogen, astraight or branched alkyl with about 1-6 carbons, or an alkoxy withabout 1-10 carbons, and Y₂ is a hydrogen sulfonate, a sulfate, aquarternary nitrogen, or a carbonate. ##STR8##

Particularly preferred peroxyacid precursors with hydroxyl nitrogenderivatives as leaving group include structures illustrated by FormulasV, VI and VII. In Formula V, R₃ and R₄ are each straight or branchedchain alkyl groups with 1 to 6 carbons, or may include a lower alkylsubstituted aryl. The R₄ substituent of Formulas VI may be an aromaticring and the R₅ and R₆ substituents are straight or branchedhydrocarbons with about 1 to 6 carbons. In Formulas VII, R₈ and R₉ maybe the same or different and are preferably C₁ -C₂₀ alkyl, aryl, oralkylaryl. If alkyl, the substituent could be partially unsaturated. Thedotted lines illustrate that R₈ and R₉ may be part of the same aromaticor cycloalkyl ring. Formula V illustrates inventive precursors derivedfrom oximes. Formulas VI illustrate inventive precursors derived fromN-hydroxyimides, and Formulas VII illustrate inventive precursorsderived from amine oxides. ##STR9##

The phenoxyacetic acid illustrated by Reaction Scheme I may beesterified to include the desired leaving group in a number ofconventional ways: by treatment of the acid with an alcohol (or phenol)under usual acid catalyzed conditions, or by conversion of thephenoxyacetic acid to an acid chloride, followed by treatment with analcohol (or phenol).

A preferred condensation reaction to form a peroxyacid precursor havinga sulfonated phenyl leaving group is generally illustrated by ReactionScheme II. ##STR10##

Reaction Scheme II is preferably performed from an initial reactionmixture including four essential components: the phenoxyacetic acid,preferably obtained from Reaction Scheme I; a phenol sulfonate; a loweralkyl acid anhydride; and, an alkyl hydrocarbon solvent. The initialreaction mixture is heated and refluxed for a sufficient time to form anacid by-product which is removed by distillation. The sulfonated phenylester reaction product (i.e., an inventive peroxyacid precursor) isformed in this preferred, one-pot synthesis. Such a synthesis isdescribed in pending U.S. Patent Application Ser. No. 915,133, filedOct. 3, 1986, now U.S. Pat. No. 4,735,740, issued Apr. 5, 1988 entitled"DIPEROXYACID PRECURSORS AND METHOD", of common assignment herewith, andincorporated by reference herein. Example I also particularly describessuch a reaction.

When a hydroxyl nitrogen compound is utilized in forming the leavinggroup of the peroxyacid precursor, then a condensation reaction the sameas or analogous to Examples III-VII may be performed.

The phenoxyacetate peroxyacid precursors of the invention permitconsiderable flexibility in choice of leaving groups, as they giveenhanced amounts of peroxyacid with respect to precursors without thenecessary α-phenoxy substitution. This is illustrated by the excellentperhydrolysis of three peroxyacid precursors of this invention withthree different leaving groups (the preparations of which are more fullydescribed in Examples II, III and IA, respectively). These threeinventive peroxy precursors were each dissolved (with the aid ofsurfactant, if necessary) in a 0.02 M carbonate buffer, pH 10.5, 21° C.,in a 2:1 ratio of peroxide source to ester group, and then each testedfor yield of peroxyacid after five minutes. Each solution was calculatedas providing a theoretical 14 ppm A.0. The results are set out in TableI.

                  TABLE I                                                         ______________________________________                                        Compound Structure      % Perhydrolysis                                       ______________________________________                                         ##STR11##              97                                                     ##STR12##              86                                                     ##STR13##              92                                                    ______________________________________                                    

As can be seen from the data of Table I, Inventive Composition (1),which illustrates a peroxyacid precursor of the invention including twoα-substituted carbonyl moieties and a derivatized resorcinol bridge,provides 97% hydrolysis. By contrast, a compound was prepared with thesame derivatized resorcinol bridge, but without the α- phenoxysubstituent, was tested in an analogous manner, and was found to provideless than 10% perhydrolysis.

It has been found that an unsubstituted ring of the phenoxy moiety givesbetter perhydrolysis performance than a hydroalkyl substituent on thering with 6 or 8 carbons, although substituents with up to 5 carbonsgive excellent perhydrolysis performance also. There is a surprisingdifference in perhydrolysis performance between compounds of theinvention, and compounds with an alkyl substituent on the ring ofgreater than 5 carbons, as is illustrated by the data of Table II.

The experiment from which the Table 11 data was taken was performed asfollows. The peroxyacid precursors were prepared, and then dissolved(with the aid of surfactant, if necessary) in a 0.02 M carbonate buffer,pH 10.5, 21° C., in a 2:1 ratio peroxide source to ester group, andtested for yield of peroxyacid after five minutes. The solutions wereprepared by calculating the amount of peroxyacid precursor required toprovide a theoretical 14 ppm A.O. Similarly, two comparison compositions(where R was 6 or 8) were prepared and tested.

                  TABLE II                                                        ______________________________________                                        Compound Structure      % Perhydrolysis                                       ______________________________________                                         ##STR14##                                                                    R = H                   92                                                    R = 4 (tertiary)        83                                                    R = 5                   86                                                    R = 6                   15                                                    R = 8 (tertiary)        26                                                    ______________________________________                                    

The dramatically better perhydrolysis of the compounds illustrated inTable II where R is hydrogen, t-butyl or pentyl with respect to thecompounds having a hexyl or a t-octyl substituent is particularlysurprising because aliphatic peroxyacids with 8 to 12 carbons (with aphenol sulfonate leaving group) give good perhydrolysis.

The peroxyacid precursors are usefully formulated with a solid source ofperoxide, such as an alkaline peroxide, in an amount effective toperhydrolyze the peroxyacid precursor, and thus to provide effectivebleaching. Suitable sources of peroxide include sodium perboratemonohydrate, sodium perborate tetrahydrate, sodium carbonateperoxyhydrate, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate,sodium peroxide, and mixtures thereof. Sodium perborate monohydrate andsodium perborate tetrahydrate are particularly preferred alkalineperoxides for combination with the peroxyacid precursors as a dry bleachcomposition or, when surfactant is included, as a dry laundering andbleaching composition.

The source of peroxide (that is, compounds yielding hydrogen peroxide inan aqueous solution) itself constitutes a peroxygen bleaching compound.However, bleach compositions including peroxyacid precursor and peroxidesource together provide better bleaching, particularly at temperaturesbelow about 60° C., than the peroxide source alone. The range ofperoxide to peroxyacid precursor is preferably determined as a molarratio of peroxide to ester groups contained in the precursor. Thus, withmonoester or diester precursors, the range of peroxide to each estergroup is a molar ratio of from about 1:1 to 10:1, more preferably about2:1 to 5:1.

The desirably high perhydrolysis profiles of the inventive perhydrolysissystem are coupled with a desirably low to moderate hydrolysis profile.Thus, the inventive perhydrolysis system preferentially forms thedesired peroxyacid when dissolved in water.

When phenol sulfonate derivatives are utilized as the leaving group,care should be taken to avoid exposure to moisture during storage priorto use in wash water. This is because such compounds tend to behygroscopic. One preferred way to solve this potential problem ofstorage stability is to coat granules of the peroxyacid precursor withone or more of a wide variety of surfactants (e.g. a nonionicsurfactant, an anionic surfactant or a cationic surfactant).

When coating with a surfactant, it is preferred to select a surfactantthat is solid at room temperatures but melts at temperatures above about40° C. A melt of surfactant may be simply admixed with peroxyacidprecursors, cooled and chopped into granules. Exemplary such surfactantsare illustrated in Table III.

                  TABLE III                                                       ______________________________________                                        Commercial Name                                                                            m.p.    Type       Supplier                                      ______________________________________                                        Pluronic F-98                                                                              55° C.                                                                         Nonionic   BASF Wyandotte                                Neodol 25-30 47° C.                                                                         Nonionic   Shell Chemical                                Neodol 25-60 53° C.                                                                         Nonionic   Shell Chemical                                Tergitol-S-30                                                                              41° C.                                                                         Nonionic   Union Carbide                                 Tergitol-S-40                                                                              45° C.                                                                         Nonionic   Union Carbide                                 Pluronic 10R8                                                                              46° C.                                                                         Nonionic   BASF Wyandotte                                Pluronic 17R8                                                                              53° C.                                                                         Nonionic   BASF Wyandotte                                Tetronic 90R8                                                                              47° C.                                                                         Nonionic   BASF Wyandotte                                Amidox C5    55° C.                                                                         Nonionic   Stepan                                        ______________________________________                                    

Surfactant coatings are also desirable when the peroxyacid precursorsinclude leaving groups other than phenol sulfonate derivatives (e.g.derivatized oximes, N-hydroxyimides and the like) to ensure that theperoxyacid precursor is solubilized fully in aqueous solution during anearly part of the wash cycle.

Peroxyacid precursors of the invention dissolved in sufficient wateralong with a source of peroxide give excellent stain removal. Thus,diagnostic evaluations of oxidant performance were performed with 100%cotton swatches stained with crystal violet as follows. Crystal violet(0.125 g) was added to 1.25 liters of distilled water. Two-inch xtwo-inch undyed, 100% cotton swatches were added to the solution andagitated for eight hours. The cotton swatches (now dyed with crystalviolet) were removed from the staining solution and rinsed repeatedlywith cold tap water until the effluent was nearly clear and allowed toair dry. All swatches were read pre- and post-wash on a HunterSpectrocolorimeter set at 10°, illuminant D. Treatments that includeddetergent were read with Uv filters in place. Experiments were carriedout in beakers with five swatches in 200 ml of solution. The solutionswere stirred on a magnetic stir plate. Respective peracid precursors andhydrogen peroxide were was allowed to dissolve for 30 seconds beforeswatches were added. At the end of a ten-minute wash, the swatches wererinsed under the deionized water tap and then air dried.

Three peroxyacids of the invention were used to wash such stained cottonswatches, and the stain removal performances were evaluated. Theperformance results are summarized in Table IV.

                  TABLE IV                                                        ______________________________________                                                                 % Stain                                                                       Removal                                              Precursor Structure      (14 ppm A.O.)                                        ______________________________________                                         ##STR15##                                                                    R = H                    97                                                   R = 4 (tertiary)         94                                                   R = 5                    92                                                   ______________________________________                                    

By contrast, hydrogen peroxide alone (in sufficient quantity to provide28 ppm) provided only 32% stain removal. This illustrates that theperhydrolysis system provides better bleaching than the peroxide sourcealone, although hydrogen peroxide by itself constitutes a peroxygenbleaching compound.

When the bleaching compositions are also laundering compositions (thatis, are admixed with detergent in addition to or without the earlierdescribed surfactant coating), then it is preferred that the amount ofperhydrolysis system, or peroxygen bleach composition in such acombination, be from about 1 wt. % to about 20 wt. % of the totalcomposition, and preferably from about 5 wt. to about 10 wt. %.

The peroxygen bleach composition (including the peroxyacid precursor anda source of peroxide), when used as a bleaching and launderingcomposition, may be formulated with a wide variety of differentdetergents, and the well known dry anionic, cationic, non-ionic,ampholytic or zwitterionic detergents, or mixtures of such detergents,are suitable. A few examples are described below.

Useful anionic detergents include, for example, the water-soluble salts(e.g., alkali metal, ammonium and alkyl ammonium salts) of organicsulfuric reaction products having in their molecular structure an alkylgroup containing from about 10 to about 20 carbon atoms and a sulfonicacid or sulfuric acid ester group, such as the sodium and potassiumalkyl sulfates and the alkyl benzene sulfonates.

Suitable nonionic detergent for use in a dry laundering composition ofthe invention include the polyethylene oxide condensates of alkylphenols, the condensation products of aliphatic alcohols with from about1 to about 25 moles of ethylene oxide, and the like.

Suitable zwitterionics include derivatives of secondary and tertiaryamines, derivatives of heterocyclic secondary and tertiary amines, orderivatives of quaternary ammonium, quaternary phosphonium or tertiarysulfonium compounds.

Useful cationics include the alkyl quaternary ammonium surfactants.

Compositions in accordance with the invention may also include one ormore laundry adjuvants such as detergent builders, buffering agents,enzymes, and minor amounts of other water-soluble solid materials suchas wetting agents, dyes and perfumes. Buffering agents can be utilizedto maintain an alkaline pH of the bleaching and/or laundering solutions,since the peroxygen bleach composition of the invention is mosteffective at a pH of about 9.0 to about 10.5.

Some of the peroxyacetate peroxy precursors are solid and others liquidat ambient temperatures. The liquid precursors may be packaged in onecompartment of a dual dispensing device, such as described in U.S. Pat.No. 4,585,150, inventors Beacham et al., issued Apr. 29, 1986, with thesource of peroxide (liquid or solid) in the other compartment.Alternatively, the liquid precursors may be dissolved in a volatilenon-nucleophilic solvent (such as an alcohol, acetone, a low molecularweight hydrocarbon, or the like) and sprayed onto an inert, solidsubstrate (such as sodium chloride, sodium sulfate, sodium borate or azeolite).

Examples IA-B through VII illustrate preparations of inventiveembodiments.

EXAMPLE IA

A five-liter three-neck Morton flask was equipped with a paddle stirrer,condenser, drying tube and heating mantle. Into this flask was added1400 ml Isopar M (isoparaffinic solvent available from ExxonCorporation) and heated to about 150°-160° C. To this was added aceticanhydride (243 g), p-phenol sulfonate (414 g), sodium acetate (10 g) andphenoxyacetic acid (304 g). This mixture was stirred very rapidly andkept at the elevated temperature overnight. A Dean-Stark trap was addedbetween the reaction flask and condenser, and a thermometer was added tothe flask. The acetic acid byproduct was removed until the temperaturerose to 206° C. (the initial temperature was 146° C. when distillatebegan to appear in the Dean-Stark trap).

The reaction mixture was allowed to cool and was filtered to give a tansolid. The solid was washed with ether (about 800 ml) on the filter pad.The solid was transferred to a two-liter flask, ether (about 700 ml)added, was stirred, refiltered, and air dried. The crude reactionproduct showed very little hydroxyl with IR analysis and a carbonyl at1780 cm⁻¹. The crude, air dried material gave 731.2 g of solid. Thiscrude material was then purified and analyzed by several techniques.

The crude solid was dissolved in hot H₂ O/MeOH (50/50 v/v, 3,000 ml),then stirred in a five-liter Morton flask in an ice bath until theinternal temperature was 7° C. The resulting thick slurry was filtered,and then let air dry overnight. The purified dried (vacuum oven, 110°C.) solid showed no hydroxyl by IR and showed two carbonyls at 1760 cm⁻¹and 1790 cm⁻¹. HPLC showed 98.7% ester, phenol sulfonate 2.0%, and noacetate ester or phenoxyacetic acid. The purified product so preparedhad the following structure: ##STR16##

Analysis by ¹³ C-nmr (DMSO, ppm downfield from TMS) showed onlyabsorbances necessary for the product. Using the numbering system shown,these assignments are made: C₁₄ (167.9), C₁ (157.6), C₇ (150.2), C₁₀(145.7), C₃,5 (129.7), C₉,11 (127.3), C₄ (121.6), C₈,12 (121.2), C₂,6(114.7) and C₁₃ (64.7).

EXAMPLE IB

A 500 ml three-neck flask was fitted with a paddle stirrer, condenser,and then lowered into an oil bath. To the flask was added distilledwater (250 ml) and sodium hydroxide (20 g, 0.5 mole) stirring until alldissolved. The 4-t-butylphenol (37.6 g, 0.25 mole) was added andstirring was continued until solution was complete. To this was addedchlororatic acid (23.6 g, 0.25 mole) and the resulting solution refluxedfor three hours. Hydrochloric acid (approximately 21 ml of 37.5%) wasadded until the pH of the solution was about one. A yellow oil thenprecipitated from solution and cooling the reaction flask in an ice-bathgave a yellow solid. The slurry was filtered and the yellow solid driedto give 47.3 g of material.

Thin layer chromotographic analysis of the crude material (Si-gel,Hx-ETAC, 80-20) showed a small yellow spot at Rf=0.81, a small amount ofresidual 4-tbutylphenol at Rf=0.51, and the product acid at Rf=0.20. Thecrude solid was dissolved in Hx-CH₂ Cl₂ (50--50, 200 ml) and placed on acolumn of silica gel (200 g, 230-400 mesh, 4 cm diameter x 43 cm high)packed with the same solvent mix. The column was eluted with Hx-CH₂ Cl₂(55 ml), CH₂ Cl₂ (600 ml), and finally Hx-ETAC (80-20, 1800 ml).Fractions from the latter column eluent were combined and the solventevaporated to give a white solid (21.4 g). This solid had m.p.86.5°-87.5° C. and the infrared spectrum showed a strong carbonyl at1710 cm⁻¹ and absence of any hydroxyl absorption in the 3500 cm⁻¹region. Analysis via titration gave a purity of 99.4%. The structure ofthis 4-t-butylphenoxy acetic acid intermediate is illlustrated below:##STR17##

The ¹³ C-NMR showed only those chemical shifts expected for the product.The assignments are shown in the structure: C₁ (155.1), C₂,6 (114.0),C₃,5 (126.2), C₄ (144.5), C₇ (33.9), C₈ (31.3), C₉ (64.7), and C₁₀(174.9). The shifts are downfield from TMS in CDCl₃ solvent. 3

A 500 ml three-neck Morton flask was fitted with a paddle stirrer,condenser with drying tube, and heating mantle. Dodecane (200 ml) wasadded to the flask and heated to approximately 140° C. The4-t-butylphenoxyacetic acid (15.0 g., 0.072 was added with rapidstirring and after it melted, the acetic anhydride (8.0 ml, 0.085 mole),anhydrous p-phenolsulfonate (15.0 g, 0.076 mole), and sodium sulfate(0.4 g, 0.005 mole) were added. The mixture was heated with constantstirring for 18 hours.

At the end of this time, a Dean-Stark trap was inserted between theflask and condenser. The acetic acid was allowed to azeotrope out (5hours) and the slurry cooled to room temperature. The slurry wasfiltered and the tan solid washed with ether (3×400 ml), and air driedon the filter pad to give 25.9 g of a light tan solid.

A portion of this solid (20.0 g) was recrystallized from MeOH-H₂ O(50--50, 120 ml). The resulting solid was dried in a vacuum over (110°C.) overnight to give a white solid (14.4 g). This solid showed a strongcarbonyl at 1780 cm⁻¹ in the infrared solution. Analysis by HPLC showedit to be 91.5% pure. The structure of the inventive sodium(p-phenylsulfonate)-4-t-butylphenoxyacetate is shown below: ##STR18##

The ¹³ C-NMR showed those chemical shifts expected for the product. Theassignments are shown in the structure: C₁ (155.0), C₂,6 (113.8), C₃,5(125.8), C₄ (143.8), C₇ (149.6), C₈,12 (120.5), C₉,11 (126.7), C₁₀(145.7), C₁₃ (64.6), C₁₄ (167.4), C₁₅ (33.5), and C₁₆ (31.0). Thechemical shifts are downfield from TMS in DMSO solvent.

EXAMPLE II

A 500 ml three-neck round bottom flask was equipped with paddle stirrer,condenser and drying tube and flushed with nitrogen. THF (150 ml),resorcinol (15 g), pyridine (21.4 g) and phenoxyacetyl chloride (46.5 g)were admixed and 50 ml additional THF added. The mixture was heated toabout 60° C. for almost three hours. The THF was stripped off and ayellow oil recovered. The oil was dissolved in CH₂ Cl₂ (200 ml) andplaced in a one-liter separatory funnel and extracted with 5% Na₂ CO₃(2×200 ml), then washed with water (200 ml) and dried over magnesiumsulfate. The magnesium sulfate was then filtered off and the solutionevaporated to obtain a orange-yellow oil. After sitting for a fewminutes, the oil solidified to a cream-colored solid. IR analysis showedno hydroxyl present and two carbonyls at 1780 cm⁻¹ and 1790 cm⁻¹. Thinlayer chromatography (with silica gel, either CH₂ Cl₂ or Hx-ETAC (80-20), UV visualization) showed one spot and a small spot at the origin.

A short column packed with silica gel (100 g, 230-400 mesh, 4 cm D×20 cmH) was prepared with CH₂ Cl₂ as liquid carrier. The yellow solid,dissolved in CH₂ Cl₂ (about 80 ml), was placed on the column and elutedto recover light yellow solid.

The solid from the column was dissolved in hot ethanol (about 300 ml),cooled in an ice bath to 15° C., and filtered. The light yellow solidwas permitted to air dry and then put in a vacuum oven at 50° C.overnight. This dried material gave a melting point of 84.5°-85.5° C.Thin layer chromatography (methylene chloride, silica gel) showed onlyone spot (R_(f) =0.52) with no spots at the origin. IR shows no hydroxylat all, and two carbonyls at 1790 cm⁻¹ and 1800 cm⁻¹.

Analysis by ¹³ C-nmr (CDCl₃, ppm downfield from TMS), showed only theabsorbances necessary for the product. Using the numbering system shownby the structure of the product, these assignments are made: C₁₄(167.0), C₇ (157.6), C₁,3 (150.4), C₅ (129.8), C₉,11 (129.6), C₁₀(121.9), C₄,6 (119.0), C₂ (114.9), C₈,12 (114.7) and C₁₃ (65.1). Thestructure of this product is illustrated as follows. ##STR19##

EXAMPLE III

A 500 ml three-neck flask was fitted with condenser, drying tube, paddlestirrer and flushed with nitrogen. Acetone oxime (14.6 g) and THF (100ml) were added with stirring. Pyridine (15.8 g) was then added.Phenoxyacetyl chloride (34.1 g) was then added, as was an additional 50ml THF. The reaction mixture was heated to 60° C. for three hours andthen cooled. White solid was filtered from the cooled reaction mixtureand was filtered off. The solvent was then stripped off to obtain alight golden oil. IR analysis of the oil showed a strong carbonyl at1780 cm⁻¹ and no hydroxyl present.

The crude oil was purified by chromatography with Hx-ETAC (80-20) ascarrier on a column of silica gel G (150 g, 230-40.0 mesh, 4 cm diameter×31 cm high). The Hx-ETAC was stripped off to give a solid with amelting point of 63.0°-64.0° C. IR analysis showed a very strongcarbonyl at 1785 cm⁻¹, no hydroxyl. ¹³ C-nmr was clean and showed onlythe absorbances expected for the product (CDCl₃, ppm downfield fromTMS). Using the numbering system shown on the product structure, theseassignments are made: C₈ (165.8), C₉ (164.0), C₁ (156.8), C₃,5 (128.5),C₄ (120.5), C₂,6 (113.6), C₇ (63.6), C₁₀ (20.4) and C₁₁ (15.5). An HPLCanalysis of the product showed it to be 98.8% pure. This product has thestructure illustrated below: ##STR20##

EXAMPLE IV

In a procedure analagous to that of Example III, phenoxyacetyl chloride(38.6 g), methyl ethyl ketoxime (19.7 g) and pyridine (17.8 g) werereacted in THF solvent with an oil bath of 60°-70° C. The crude productwas purified by chromatography over silica gel 60 (200 g, 230-400 mesh,4 cm diameter and 41 cm high) in 50-50 Hx-CH₂ Cl₂. IR analysis of thepurified product showed one large carbonyl at 1782 cm⁻¹ , no sign of anyhydroxyl. The ¹³ C-nmr showed only those absorbances necessary for theproduct (CDCl₃, ppm downfield from TMS) Using the numbering systemshown, these assignments are made: C₉ config. (168.7), C₉ major config.(167.8), C₈ (166.3), C₁ (157.0), C₃,5 (128.7), C₄ (120.8), C₂,6 (113.8),C₇ (63.9), C₁₁ major config. (28.4), C₁₁ minor config. (23.0), C₁₀ minorconfig. (18.4), C₁₀ major config. (14.0), C₁₂ major config. (9.7) andC₁₂ minor config. (9.2). The minor and major structural configurationsof this product are illustrated below: ##STR21##

EXAMPLE V

In a 500 ml three-neck flask fitted with paddle stirrer, condenser anddrying tubes are added n- hydroxysuccinimide (11.5 g), phenoxyacetylchloride (17.0 g) and pyridine (7.9 g) in about 250 ml THF. The reactionmixture is heated for about three hours at 60° C. As with the crudeproducts of Examples III and IV, this crude product may also be purifiedwith a silica gel column using a CH₂ Cl₂ solution. The structure of thisproduct is illustrated as follows: ##STR22##

EXAMPLE VI

A 500 ml three-neck flask is fitted with paddle stirrer, condenser anddrying tube. N-hydroxyphthalimide (16.3 g), pyridine (7.9 g) andphenoxyacetyl chloride (17.0 g) are reacted in 250 ml THF solvent in ananalogous manner to Example v. The crude reaction product may bepurified over a silica gel column. The structure of the resultantproduct is illustrated below: ##STR23##

EXAMPLE VII A 500 ml three-neck flask was fitted with a paddle stirrer,drying tube and flushed with nitrogen. To the flask is added THF (150ml) and 4-phenylpyridine N-oxide (5 g). A light yellow solution results.To this is added rapidly phenoxyacetyl chloride (4.9 g) in THF (20 ml).The mixture is stirred very rapidly for about 11/2 minutes. A gelatinousprecipitate forms almost immediately. When the viscous solution isdiluted with ether (less than 300 ml), a white solid layer separates.The mix is filtered to give a white solid, which is washed with etherand dried. The structure of the product is illustrated as follows:##STR24##

While the invention has been described in connection with specificembodiments thereof, it will be understood that it is capable of furthermodifications, and this application is intended to cover any variations,uses or adaptations of the invention following, in general, theprinciples of the invention and including such departures from thedisclosure as come within the known or customary practice in the art towhich the invention pertains and as may be applied to the essentialfeatures hereinbefore set forth, and as fall within the scope of theinvention and the limits of the appended claims.

What is claimed:
 1. A perhydrolysis system for in situ generation ofperoxyacid comprising:a peroxyacid precursor including at least oneα-substituted carbonyl moiety with the structure ##STR25## wherein R ishydrogen or an alkyl with not more than 5 carbons and L is a group whoseconjugate acid has a pKa in aqueous solution of between about 5 to about13; and a source of peroxygen which will react with the peroxyacidprecursor in aqueous solution to form a peroxyacid having the structure##STR26##
 2. The perhydrolysis system as in claim 1 wherein L isselected from the group consisting of ##STR27## wherein R₂ is hydrogen,a straight or branched alkyl with about 1-6 carbons or an alkoxy withabout 1-10 carbons, and Y₂ is a sulfate, a carbonate, or a quarternarynitrogen.(c) --ON═CR₃ R₄ wherein R₃ and R₄ are each straight or branchedchain alkyl with 1 to 6 carbons, an aryl or a cycloaryl; ##STR28##wherein R₅ is hydrogen or an aromatic ring; ##STR29## wherein R₆ and R₇straight or branched hydrocarbons with about 1 to 6 carbons; and,##STR30## wherein R₈ and R₉ are alkyl, aryl, or alkylaryl with about 1to 20 carbons and may be part of the same aromatic or cycloalkyl ring.3. The perhydrolysis system as in claim 1 wherein the peroxyacidprecursor has the structure ##STR31##
 4. The perhydrolysis system as inclaim 1 wherein the peroxyacid precursor has the structure ##STR32##wherein Y is a substituted or unsubstituted aromatic ring.
 5. Theperhydroxylsis system as in claim 4 wherein a substituent of thearomatic ring is one or more of a sulfonate, a sulfate, a carbonate, aquaternary nitrogen, an alkoxy of about 1 to 10 carbons, or an alkyl ofabout 1 to 6 carbons.
 6. The perhydrolysis system as in claim 5 whereinthe peroxyacid precursor has the structure ##STR33## wherein M ishydrogen, an alkali metal, an alkaline earth metal, or ammonium.
 7. Theperhydrolysis system as in claim 5 wherein the peroxyacid precursor hasthe structure ##STR34## wherein Z is selected from the group consistingof an oxime, an N-hydroxyimide, or an amine oxide.
 8. The perhydrolysissystem as in claim 7 wherein the peroxygen precursor has the structure##STR35## wherein R₃ and R₄ are each straight or branched chain alkylwith 1 to 6 carbons, an aryl, or a cycloalkyl.
 9. The perhydrolysissystem as in claim 7 wherein the peroxygen precursor has the structure##STR36## wherein R₅ is hydrogen or an aromatic ring, and R₆ and R₇ arestraight or branched hydrocarbons with about 1 to 6 carbons.
 10. Theperhydrolysis system as in claim 7 wherein the peroxyacid precursor hasthe structure ##STR37## wherein R₈ and R₉ are alkyl, aryl, or alkylarylwith about 1 to 20 carbons and may be part of the same aromatic orcycloalkyl ring.
 11. The perhydrolysis system as in claim 1 wherein thereaction between peroxygen source and peroxyacid precursor yields atleast about 75% of the peroxyacid from the peroxyacid precursor in a 21°C. aqueous solution at a pH of 9.5 when the peroxygen source is at leastequimolar with the number of α-substituted carbonyl moieties of theperoxyacid precursor.
 12. The perhydrolysis system as in claim 1 furthercomprising nonionic or anionic surfactant in an amount sufficient tosolubilize fully the peroxyacid precursor in aqueous solution.
 13. Theperhydrolysis system as in claim 12 wherein the surfactant has a meltingpoint of not less than about 40°C.
 14. The perhydrolysis system as inclaim 12 wherein the peroxyacid precursor is in granular form, and thesurfactant is coated on granules thereof.
 15. The perhydrolysis systemas in claim 11 further comprising an alkaline buffering agent.
 16. Theperhydrolysis system as in claim 1 wherein the peroxygen source isselected from the group consisting of sodium perborate monohydrate,sodium perborate tetrahydrate, sodium carbonate peroxyhydrate, sodiumpyrophosphate peroxyhydrate, urea peroxyhydrate, sodium peroxide ormixtures thereof.
 17. The perhydrolysis system as in claim 4 or 5wherein the peroxygen precursor is coated with a surfactant.